Initial refactoring into USB class

Clean up and make the USB subsystem design into a class instead of
a collection of C functions which share static local state.

Author: earlephilhower

cores/rp2040/RP2040USB.cpp

@@ -34,13 +34,21 @@
 #include <pico/usb_reset_interface.h>
 #include <hardware/watchdog.h>
 
+#ifdef __FREERTOS
+#include "FreeRTOS.h"
+#include "task.h"
+#include "timers.h"
+#include "semphr.h"
+#endif
+
+RP2040USB USB;
+
 // Big, global USB mutex, shared with all USB devices to make sure we don't
 // have multiple cores updating the TUSB state in parallel
 mutex_t __usb_mutex;
 
 // USB processing will be a periodic timer task
 #define USB_TASK_INTERVAL 1000
-static int __usb_task_irq;
 
 #ifndef USBD_VID
 #define USBD_VID (0x2E8A) // Raspberry Pi
@@ -108,7 +116,7 @@ static int ffs(uint32_t v) {
     return 0;
 }
 
-uint8_t usbRegisterEndpointIn() {
+uint8_t RP2040USB::registerEndpointIn() {
     if (!_endpointIn) {
         return 0; // ERROR, out of EPs
     }
@@ -117,11 +125,11 @@ uint8_t usbRegisterEndpointIn() {
     return 0x80 + firstFree;
 }
 
-void usbUnregisterEndpointIn(int ep) {
+void RP2040USB::unregisterEndpointIn(int ep) {
     _endpointIn |= 1 << ep;
 }
 
-uint8_t usbRegisterEndpointOut() {
+uint8_t RP2040USB::registerEndpointOut() {
     if (!_endpointOut) {
         return 0; // ERROR, out of EPs
     }
@@ -130,7 +138,7 @@ uint8_t usbRegisterEndpointOut() {
     return firstFree;
 }
 
-void usbUnregisterEndpointOut(int ep) {
+void RP2040USB::unregisterEndpointOut(int ep) {
     _endpointOut |= (1 << (ep - 0x80));
 }
 
@@ -198,33 +206,33 @@ static unsigned int usbFindID(Entry *head, unsigned int localid) {
     return x;
 }
 
-uint8_t usbFindHIDReportID(unsigned int localid) {
+uint8_t RP2040USB::findHIDReportID(unsigned int localid) {
     return usbFindID(_hids, localid) + 1; // HID reports start at 1
 }
 
-uint8_t usbFindInterfaceID(unsigned int localid) {
+uint8_t RP2040USB::findInterfaceID(unsigned int localid) {
     return usbFindID(_interfaces, localid);
 }
 
 // Called by a HID device to register a report.  Returns the *local* ID which must be mapped to the HID report ID
-uint8_t usbRegisterHIDDevice(const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask) {
+uint8_t RP2040USB::registerHIDDevice(const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask) {
     return AddEntry(&_hids, 0, descriptor, len, ordering, vidMask);
 }
 
-void usbUnregisterHIDDevice(unsigned int localid) {
+void RP2040USB::unregisterHIDDevice(unsigned int localid) {
     RemoveEntry(&_hids, localid);
 }
 
 // Called by an object at global init time to add a new interface (non-HID, like CDC or Picotool)
-uint8_t usbRegisterInterface(int interfaces, const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask) {
+uint8_t RP2040USB::registerInterface(int interfaces, const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask) {
     return AddEntry(&_interfaces, interfaces, descriptor, len, ordering, vidMask);
 }
 
-void usbUnregisterInterface(unsigned int localid) {
+void RP2040USB::unregisterInterface(unsigned int localid) {
     RemoveEntry(&_interfaces, localid);
 }
 
-uint8_t usbRegisterString(const char *str) {
+uint8_t RP2040USB::registerString(const char *str) {
     if (usbd_desc_str_alloc <= usbd_desc_str_cnt) {
         usbd_desc_str_alloc += 4;
         usbd_desc_str = (const char **)realloc(usbd_desc_str, usbd_desc_str_alloc * sizeof(usbd_desc_str[0]));
@@ -246,22 +254,22 @@ uint8_t usbRegisterString(const char *str) {
 
 static uint16_t _forceVID = 0;
 static uint16_t _forcePID = 0;
-void usbSetVIDPID(uint16_t vid, uint16_t pid) {
+void RP2040USB::setVIDPID(uint16_t vid, uint16_t pid) {
     _forceVID = vid;
     _forcePID = pid;
 }
 
 static uint8_t _forceManuf = 0;
 static uint8_t _forceProd = 0;
 static uint8_t _forceSerial = 0;
-void usbSetManufacturer(const char *str) {
-    _forceManuf = usbRegisterString(str);
+void RP2040USB::setManufacturer(const char *str) {
+    _forceManuf = USB.registerString(str);
 }
-void usbSetProduct(const char *str) {
-    _forceProd = usbRegisterString(str);
+void RP2040USB::setProduct(const char *str) {
+    _forceProd = USB.registerString(str);
 }
-void usbSetSerialNumber(const char *str) {
-    _forceSerial = usbRegisterString(str);
+void RP2040USB::setSerialNumber(const char *str) {
+    _forceSerial = USB.registerString(str);
 }
 
 static tusb_desc_device_t usbd_desc_device;
@@ -282,9 +290,9 @@ const uint8_t *tud_descriptor_device_cb(void) {
         .idVendor = _forceVID ? _forceVID : (uint16_t)USBD_VID,
         .idProduct = _forcePID ? _forcePID : (uint16_t)USBD_PID,
         .bcdDevice = 0x0100,
-        .iManufacturer = _forceManuf ? _forceManuf : usbRegisterString(USB_MANUFACTURER),
-        .iProduct = _forceProd ? _forceProd : usbRegisterString(USB_PRODUCT),
-        .iSerialNumber = _forceSerial ? _forceSerial : usbRegisterString(idString),
+        .iManufacturer = _forceManuf ? _forceManuf : USB.registerString(USB_MANUFACTURER),
+        .iProduct = _forceProd ? _forceProd : USB.registerString(USB_PRODUCT),
+        .iSerialNumber = _forceSerial ? _forceSerial : USB.registerString(idString),
         .bNumConfigurations = 1
     };
 
@@ -373,14 +381,14 @@ void __SetupUSBDescriptor() {
     if (GetDescHIDReport(&hid_report_len)) {
         uint8_t hid_desc[TUD_HID_DESC_LEN] = {
             // Interface number, string index, protocol, report descriptor len, EP In & Out address, size & polling interval
-            TUD_HID_DESCRIPTOR(1 /* placeholder*/, 0, HID_ITF_PROTOCOL_NONE, hid_report_len, __hid_endpoint = usbRegisterEndpointIn(), CFG_TUD_HID_EP_BUFSIZE, (uint8_t)usb_hid_poll_interval)
+            TUD_HID_DESCRIPTOR(1 /* placeholder*/, 0, HID_ITF_PROTOCOL_NONE, hid_report_len, __hid_endpoint = USB.registerEndpointIn(), CFG_TUD_HID_EP_BUFSIZE, (uint8_t)usb_hid_poll_interval)
         };
-        __hid_interface = usbRegisterInterface(1, hid_desc, sizeof(hid_desc), 10, 0);
+        __hid_interface = USB.registerInterface(1, hid_desc, sizeof(hid_desc), 10, 0);
     }
 
 #ifdef ENABLE_PICOTOOL_USB
-    uint8_t picotool_desc[] = { TUD_RPI_RESET_DESCRIPTOR(1, usbRegisterString("Reset")) };
-    usbRegisterInterface(1, picotool_desc, sizeof(picotool_desc), 100, 0);
+    uint8_t picotool_desc[] = { TUD_RPI_RESET_DESCRIPTOR(1, USB.registerString("Reset")) };
+    USB.registerInterface(1, picotool_desc, sizeof(picotool_desc), 100, 0);
 #endif
 
     usbd_desc_cfg_len = TUD_CONFIG_DESC_LEN; // Always have a config descriptor
@@ -393,7 +401,7 @@ void __SetupUSBDescriptor() {
 
     uint8_t tud_cfg_desc[TUD_CONFIG_DESC_LEN] = {
         // Config number, interface count, string index, total length, attribute, power in mA
-        TUD_CONFIG_DESCRIPTOR(1, interface_count, usbRegisterString(""), usbd_desc_cfg_len, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, USBD_MAX_POWER_MA)
+        TUD_CONFIG_DESCRIPTOR(1, interface_count, USB.registerString(""), usbd_desc_cfg_len, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, USBD_MAX_POWER_MA)
     };
 
     // Allocate the "real" HID report descriptor
@@ -441,7 +449,28 @@ const uint16_t *tud_descriptor_string_cb(uint8_t index, uint16_t langid) {
     return desc_str;
 }
 
+#ifdef __FREERTOS
+void __freertos_usb_task(void *param) {
+    (void) param;
+
+    Serial.begin(115200);
+
+    USB.initted = true;
 
+    while (true) {
+        BaseType_t ss = xTaskGetSchedulerState();
+        if (ss != taskSCHEDULER_SUSPENDED) {
+            auto m = __get_freertos_mutex_for_ptr(&__usb_mutex);
+            if (xSemaphoreTake(m, 0)) {
+                tud_task();
+                xSemaphoreGive(m);
+            }
+        }
+        vTaskDelay(1 / portTICK_PERIOD_MS);
+    }
+}
+#else
+static int __usb_task_irq;
 static void usb_irq() {
     // if the mutex is already owned, then we are in user code
     // in this file which will do a tud_task itself, so we'll just do nothing
@@ -456,34 +485,40 @@ static int64_t timer_task(__unused alarm_id_t id, __unused void *user_data) {
     irq_set_pending(__usb_task_irq);
     return USB_TASK_INTERVAL;
 }
+#endif
 
-void usbDisconnect() {
+void RP2040USB::disconnect() {
+    bool wasConnected = tud_connected();
 #ifdef __FREERTOS
     auto m = __get_freertos_mutex_for_ptr(&__usb_mutex);
     xSemaphoreTake(m, portMAX_DELAY);
     tud_disconnect();
-    vTaskDelay(500 / portTICK_PERIOD_MS);
+    if (wasConnected) {
+        vTaskDelay(500 / portTICK_PERIOD_MS);
+    }
     xSemaphoreGive(m);
 #else
     mutex_enter_blocking(&__usb_mutex);
     tud_disconnect();
-    sleep_ms(500);
+    if (wasConnected) {
+        sleep_ms(500);
+    }
     mutex_exit(&__usb_mutex);
 #endif
     // Ensure when we reconnect we make the new descriptor
     free(usbd_desc_cfg);
     usbd_desc_cfg = nullptr;
     usbd_desc_cfg_len = 0;
     if (__hid_report) {
-        usbUnregisterInterface(__hid_interface);
-        usbUnregisterEndpointIn(__hid_endpoint);
+        unregisterInterface(__hid_interface);
+        unregisterEndpointIn(__hid_endpoint);
     }
     free(__hid_report);
     __hid_report = nullptr;
     __hid_report_len = 0;
 }
 
-void usbConnect()  {
+void RP2040USB::connect()  {
     __SetupDescHIDReport();
     __SetupUSBDescriptor();
 
@@ -499,9 +534,12 @@ void usbConnect()  {
 #endif
 }
 
-void __USBStart() __attribute__((weak));
 
-void __USBStart() {
+
+
+
+
+void RP2040USB::begin() {
     if (tusb_inited()) {
         // Already called
         return;
@@ -514,15 +552,21 @@ void __USBStart() {
 
     tusb_init();
 
+#ifdef __FREERTOS
+    // Make high prio and locked to core 0
+    TaskHandle_t usbTask;
+    xTaskCreate(__freertos_usb_task, "USB", 256, 0, configMAX_PRIORITIES - 2, &usbTask);
+    vTaskCoreAffinitySet(usbTask, 1 << 0);
+#else
     __usb_task_irq = user_irq_claim_unused(true);
     irq_set_exclusive_handler(__usb_task_irq, usb_irq);
     irq_set_enabled(__usb_task_irq, true);
-
     add_alarm_in_us(USB_TASK_INTERVAL, timer_task, nullptr, true);
+#endif
 }
 
 
-bool __USBHIDReady() {
+bool RP2040USB::HIDReady() {
     uint32_t start = millis();
     const uint32_t timeout = 500;
 

cores/rp2040/RP2040USB.h

@@ -19,56 +19,72 @@
     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
+#pragma once
+
 #include <pico/mutex.h>
-#include <limits.h>
+//#include <limits.h>
 
-// Called by an object at global init time to register a HID device, returns a localID to be mapped using findHIDReportID
-// vidMask is the bits in the VID that should be XOR'd when this device is present.
-// 0 means don't invert anything, OTW select a single bitmask 1<<n.
-uint8_t usbRegisterHIDDevice(const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask);
+#ifdef __cplusplus
 
-// Remove a HID device from the USB descriptor.  Only call after usbDisconnect or results could be unpredictable!
-void usbUnregisterHIDDevice(unsigned int localid);
+class RP2040USB {
+public:
+    RP2040USB() { }
 
-// Called by an object at global init time to add a new interface (non-HID, like CDC or Picotool)
-uint8_t usbRegisterInterface(int interfaces, const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask);
+    // Called by an object at global init time to register a HID device, returns a localID to be mapped using findHIDReportID
+    // vidMask is the bits in the VID that should be XOR'd when this device is present.
+    // 0 means don't invert anything, OTW select a single bitmask 1<<n.
+    uint8_t registerHIDDevice(const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask);
 
-// Remove a USB interface from the USB descriptor.  Only call after usbDisconnect or results could be unpredictable!
-void usbUnregisterInterface(unsigned int localid);
+    // Remove a HID device from the USB descriptor.  Only call after usbDisconnect or results could be unpredictable!
+    void unregisterHIDDevice(unsigned int localid);
 
-// Get the USB HID actual report ID from the localid
-uint8_t usbFindHIDReportID(unsigned int localid);
+    // Called by an object at global init time to add a new interface (non-HID, like CDC or Picotool)
+    uint8_t registerInterface(int interfaces, const uint8_t *descriptor, size_t len, int ordering, uint32_t vidMask);
 
-// Get the USB interface number from the localid
-uint8_t usbFindInterfaceID(unsigned int localid);
+    // Remove a USB interface from the USB descriptor.  Only call after usbDisconnect or results could be unpredictable!
+    void unregisterInterface(unsigned int localid);
 
-// Register a string for a USB descriptor
-uint8_t usbRegisterString(const char *str);
+    // Get the USB HID actual report ID from the localid
+    uint8_t findHIDReportID(unsigned int localid);
 
-// Get an unassigned in/cmd or out endpoint number
-uint8_t usbRegisterEndpointIn();
-uint8_t usbRegisterEndpointOut();
-void usbUnregisterEndpointIn(int ep);
-void usbUnregisterEndpointOut(int ep);
+    // Get the USB interface number from the localid
+    uint8_t findInterfaceID(unsigned int localid);
 
-// Disconnects the USB connection to allow editing the HID/interface list
-void usbDisconnect();
+    // Register a string for a USB descriptor
+    uint8_t registerString(const char *str);
 
-// Reconnects the USB connection to pick up the new descriptor
-void usbConnect();
+    // Get an unassigned in/cmd or out endpoint number
+    uint8_t registerEndpointIn();
+    uint8_t registerEndpointOut();
+    void unregisterEndpointIn(int ep);
+    void unregisterEndpointOut(int ep);
 
-// Override the hardcoded USB VID:PID, product, manufacturer, and serials
-void usbSetVIDPID(uint16_t vid, uint16_t pid);
-void usbSetManufacturer(const char *str);
-void usbSetProduct(const char *str);
-void usbSetSerialNumber(const char *str);
+    // Disconnects the USB connection to allow editing the HID/interface list
+    void disconnect();
 
-// Big, global USB mutex, shared with all USB devices to make sure we don't
-// have multiple cores updating the TUSB state in parallel
-extern mutex_t __usb_mutex;
+    // Reconnects the USB connection to pick up the new descriptor
+    void connect();
+
+    // Override the hardcoded USB VID:PID, product, manufacturer, and serials
+    void setVIDPID(uint16_t vid, uint16_t pid);
+    void setManufacturer(const char *str);
+    void setProduct(const char *str);
+    void setSerialNumber(const char *str);
+
+    // Called by main() to init the USB HW/SW.
+    void begin();
 
-// Called by main() to init the USB HW/SW.
-void __USBStart();
+    // Helper class for HID report sending with wait and timeout
+    bool HIDReady();
 
-// Helper class for HID report sending with wait and timeout
-bool __USBHIDReady();
+#ifdef __FREERTOS
+    volatile bool initted = false;
+#endif
+};
+
+extern RP2040USB USB;
+
+#endif
+
+// have multiple cores updating the TUSB state in parallel
+extern mutex_t __usb_mutex;